Pull trailer and load lift means

ABSTRACT

A load supporting and lifting means for a pallet load carrying tractor-trailer assembly. The load bearing plates are supported at the upper ends of an inflatable air bag with a lower end of the bag being supported on the truck or trailer frame. Hinge load carrying plates also connect the edges of the load bearing plates to the frame of the truck or trailer. Breaking cylinders are connected between the hinge plates and the base frame to aid in load release action. The hinge plates are substantially vertically directed when operative and carry a substantial portion of the weight and stabilize the load when it has been lifted by the inflated air bag.

United States Patent 1191 1111' 3,843,092 Oehler Oct. 22, 1974 PULLTRAILER AND LOAD LIFT MEANS Prima Examiner-Othell M. Sim son 7 1w. 1 1 P61 Inventor gzz 3:22: 1 5 h Ct Attorney, Agent, or Fir m--Oldham &Oldham C 0.

[ I 'P N05 3551463 A load supporting and lifting meansfor a pallet loadRemed s Appncation Data carrying tractor-trailer assembly. The loadbearing [62] Division of Ser. No. 110 486 Jan. 28 1971 Pat No platessupported at the upper inflatable 3 752 502. air bag with a lower end ofthe bag being supported on the truck or trailer frame. Hinge loadcarrying plates also connect the edges of the load bearing plates to254/93 the frame of the truck or trailer. Breaking cylinders [58] Fieldf HP 2 are connected between the hinge plates and the base 2112. 92/3438 frame to aid in load release action. The hinge plates aresubstantially vertically directed when operative [56] References Citedand carry a substantial portion of the weight and stab lize the loadwhen 1t has been lifted by the inflated a1r UNITED STATES PATENTS bag2,610,824 9/1952 Grier 254/93 HP 3,730,366 5/1973 Berends 214/512 ZMQDQJ8 Q3935 PATENTEDBCI 22 :an 3; 843; 092 Slim 2 If 2 PULL TRAILER AND LOADLIFT-MEANS This is a division of my application Ser. No. 110,486 filedJan. 28, 1971, now US. Pat. No. 3,752,502.

The present invention relates to an improved load supporting and liftingdevice for use with a pallet load carrying tractor-trailer assembly.Tractor-trailer assemblies of this type are shown in my copendingapplication Ser. No. 61,228 now U.S. Pat. No. 3,719,299 for PALLET TYPELOAD TRANSPORT APPARATUS, filed Aug. 5, 1970. In such an arrangement,sturdy pallets are provided for load support and storage and haveretractable legs which position the pallet at a sufficient height sothat a trailer may be moved under the pallet. The tractor and trailereach include lifting devices which are then operated to raise the pallettogether with its load so that the support legs can be moved to theirinoperative position after which the pallet may be lowered onto thetractor and trailer so that it can be transported to a new site.

It is the primary object of the present invention to provide improvedload lifting and transport means for tractor-trailer pallet loadcarrying assemblies.

It is also an object of the invention to provide improved lifting meanswhich have improved lateral stability when supporting the pallet andload.

A further object of the invention is the provision of sturdy loadlifting and carrying means which are of uncomplicated, trouble-freeconstruction and operation.

The above and other objects of the invention which will become apparentin the following detailed description are achieved by providing liftingmeans which consist of an inflatable air bag or enclosure mounted on thetruck or trailer frame and supporting a pallet engaging plate on itsupper surface. Increased lifting capacity and stability are achieved byproviding hinge plates connecting each side of the load supportingplates to the truck or trailer frame. It is also contemplated thatbreaking cylinders may be connected between the hinge plates and theframe to increase the load carrying capacity and aid in load releaseaction.

For a more complete understanding of the objects and advantages of theinvention, reference should be had to the following specification andtheaccompanying drawings wherein there is shown a preferred embodimentof the invention.

In the drawing:

FIG. 1 is a side elevational view of a tractor-trailer assembly equippedwith the load supporting and lifting devices of the present invention, aload supporting pallet being shown in its lower position and in itsupper position in dotted outline;

FIG. 2 is a plan view of the tractor-trailer assembly of FIG. 1;

FIG. 3 is an enlarged sectional view taken along the line 3-3 of FIG. 2;and

FIG. 4 is a view similar to that of FIG. 3 but showing the loadsupporting and lifting assembly in its fully collapsed position.

Referring first to FIGS. 1 and 2, the reference numeral l designatesgenerally the tractor, the numeral 12 designates the trailer, and thenumeral 14 designates the load carrying pallet. The tractor is ofconventional construction and has a frame 16 and roadengaging wheels 18.The tractor 10 is provided with a fifth wheel assembly 20 which issupported on the tractor frame 16 by the supporting and lifting device22 of the present invention.

The trailer 12 has a frame 24 with road engaging wheels 26. A secondfifth wheel assembly 28 is supported on the frame 24 by a secondsupporting and lifting device 30. The trailer 12 is a pole type and isconnected to the tractor 10 by a center pole 32. A suitable hitch point34 is provided on the frame 16 of the tractor 10 for this purpose.

The load supporting pallet 14 may be the type illustrated in theabove-mentioned application. The pallet 14 has an elongated frame 36which is provided with suitable king pins, not shown, for connectionwith the fifth wheel assembly 20 of the tractor l0 and the fifth wheelassembly 28 of the trailer 12. Front and rear pairs of supporting legs38 and 40, respectively, are provided on the sides of the pallet frame36. Each of the legs 38 and 40 is retractable and may, for example,consist of outer and inner telescoping sections 38a and 38b,respectively, which are held together by pins or other suitablefastening means,-not shown. Suitable feet 380 are provided at the lowerends of the legs.

While the lifting and supporting assemblies 22 and 30 will be describedin more detail below, it should be understood that each of theseassemblies has a collapsed or lowered position, as shown in solid linesin FIG. 1 and an extended or upper position, as shown in dotted outline.Thus the supporting devices 22 and 30 are operable to raise and lowerthe associated fifth wheel assemblies 20 and 28, respectively, and thusto raise and lower the pallet 14. A pallet 14 is loaded onto thetractor-trailer assembly l0, 12 by positioning the pallet at its upperposition with its legs 38 and 40 extended. The trailer 12 and tractor 10are then maneuvered under the pallet so that the fifth wheel assemblies20, 28 are aligned with the respective king pins of the pallet 14. Itwill be understood that suitable channels or other guiding means may beprovided on the underside of the frame 36 of the pallet 14 to aid inaligning the king pins and fifth wheel assemblies. When the tractor andtrailer have been properly positioned, the lifting devices 22 and 30 areraised to their fullest extent, to engage and lift the pallet,permitting the pallet supporting legs 38 and 40 to be retracted. Thetractor l0 and trailer .12 with the pallet 14 may now be moved. When thepallet has been transported to the desired location, the above processis reversed, permitting the tractor l0 and trailer 12 to be removed fromunder the pallet 14. The tractor and trailer assembly l0, 12 is now freeto be loaded with another pallet. If desired, when the legs 38 and 40are removed or retracted, the devices 22 and 30 are collapsed for loadtransport.

The lifting device 30 of the trailer 12 is illustrated in FIGS. 3 and 4.The device 22 mounted on the tractor 10 is of identical construction. Arectangular or square base plate 42 is mounted on the trailer frame 24.A second square or rectangular plate 44 is mounted on the underside ofthe fifth wheel assembly 28, not shown in FIGS. 3 and 4. An inflatableair bag 46 is positioned between the base 42 and upper plate 44. Thelower end of the air bag 46 has an annular rib 48 which is clamped byconventional means such as a clamping ring 50 to the base 42. The upperend of the air bag 46 has an annular rib 52 which is secured to theupper plate 44 by a second clamping ring or equivalent device 54. Theribs 48 and 52 with the associated clamping rings 50 and 54 formair-tight seals between the air bag 46 and the base 42 and top plate 44,respectively. While not shown, a suitable port is provided, for examplein the base plate 42, to permit compressed air to flow into or out ofthe interior of the air bag 46. Also, suitable controlling means areprovided to regulate the flow of air into or out of the interior of theair bag 46 so that the device may be selectively raised or lowered. Itshould be noted, as shown in FlG. 3, that the cross-sectionalconfiguration of the air bag 46 is usually that of a flattened figureeight. This configuration is of importance as it permits the side wallsof the air bag 46 to fold smoothly when the bag is collapsed, as isshown in FIG. 4. It should also be noted that the air bag 46 is of alarge diameter to contribute to the stable load lifting and supportingproperties of the device.

Further load supporting and stabilizing action is achieved by a hingeplate arrangement connecting the base plate 42 and the upper or fifthwheel support plate 44. This arrangement consists of plates 56, 58, 60and 62 which are hinged to the lateral edges of the upper plate 44, oneof the hinge plates 56 to'62 being provided along each side of the topplate 44 with each of the plates extending substantially the full lengthof the top plate 44 and extending generally downwardly therefrom.Additional hinge plates 64, 66, 68 and 72 are provided on each of thefour edges of the base plate 42, with one of the hinge plates 64 to 72being provided along each side of the base plate 42 and extendingsubstantially the entire length thereof. The upper and lower hingeplates on the corresponding sides of the top plate 44 and the base plate42 are connected together by suitable piano-type hinge connection.Breaking cylinders 74 and 76 preferably are connected between the baseplate 42 and each of a pair of opposed lower hinge plates 64 and 68, theconnections of piston rods 74a of the cylinders to the hinge platesbeing made adjacent their upper ends. These cylinders 74 and 76 areactuated when the elevated top plate 44 is to be lowered to aid instarting collapse of the hinge plates 56 and 64; 60 and 68, etc. As canbe seen from P16. 3, when the air bag 46 is fully inflated, raising thetopplate 44 to its upper position the pairs of hinge plates meet at anangle usually only slightly less than 180 but which may be of a full 180so that the pairs of plates form nearly a straight line. Usually thebreaking cylinders 74 and 76 are locked while the hinge plates are inthis position, and because of the friction on the hinge means asubstantial portion of the weight carried by the top plate 44 can betransmitted to the base plate 42 and trailer frame 24 through the hingeplate arrangement. Obviously, other arrangements may be provided toachieve this locking of the hinge plates. It will be readily apparentthat since the hinge plate assemblies extend along substantially theentire length of each side of the base plate 42 and top plate 44, thesehinge plate arrangements assure the uniform and stable upward anddownward movement of the top plate 44, maintaining this top plate in aparallel relation to the base plate 42. Thus, even if the top plate 44is unevenly loaded, uniform raising and lowering of the top plate 44 andthe load carried thereby is assured.

The box-like assembly of the various hinge plates aids in stable loadsupport and transport action. Then actuation of the cylinders 74 and 76aids in obtaining an air bag release and pallet lowering action, thepallet support legs being operably positioned before, of course. Thetractor and trailer then may pull out from under a pallet and be usedfor other pallet transfer jobs. A stable, sturdy load lift and lowerunit has been provided What is claimed is: l. A load lifting andsupporting device, comprising:

a rectangular base;

a rectangular top plate located above the base and adapted to engage andsupport the load;

an inflatable enclosure positioned between the base and the top plate,the enclosure supporting the top plate;

a plurality of first hinge leaves, one leaf being hinged to each side ofthe top plate and extending generally downwardly therefrom; and

a plurality of second hinge leaves, one leaf being hinged to each sideof the base and extending generally upwardly therefrom, the lower end ofeach first leaf being hinged to the upper end of the second leaf on thecorresponding side of the base to form hinges each having an axisparallel to the side 3. The load lifting and supporting device accordingtoclaim 1 wherein the combined heights of the first and second hingeleaves is only slightly greater than the maximum separation between thebase and the top plate effected by inflation of the enclosure.

4. The load lifting and supporting device according to claim 1 whereinthe hinge leaves are angled outwardly with relation-to said enclosure atall times.

5. The load lifting and supporting device according to claim 1 whereinmeans are provided to aid in controlling the movementof at least certainof the hinge leaves when the device is elevated and the hinges are to becollapsed.

6. The load lifting and supporting device according to claim 5 whereinthe means comprises breaking cylinders and piston rod units operativelyconnected at one end to-a pair of opposed members of the second hingeleaves adjacent the upper end thereof and at the opposite end to thebase to move the hinge leaves outwardly.

7. The load lifting and supporting device according to claim 1 whereinthe operative heights of said hinges is substantially equal to themaximum separation between the base and the top plate effected bymaximum inflation of the enclosure, and said hinges maintain said topplate parallel to said base.

1. A load lifting and supporting device, comprising: a rectangular base;a rectangular top plate located above the base and adapted to engage andsupport the load; an inflatable enclosure positioned between the baseand the top plate, the enclosure supporting the top plate; a pluralityof first hinge leaves, one leaf being hinged to each side of the topplate and extending generally downwardly therefrom; and a plurality ofsecond hinge leaves, one leaf being hinged to each side of the base andextending generally upwardly therefrom, the lower end of each first leafbeing hinged to the upper end of the second leaf on the correspondingside of the base to form hinges each having an axis parallel to the sideof the base to which the second hinge leaf thereof is secured.
 2. Theload lifting and supporting device according to claim 1 wherein thehinge leaves extend along substantially the entire length of each sideof the base and of the top plate.
 3. The load lifting and supportingdevice according to claim 1 wherein the combined heights of the firstand second hinge leaves is only slightly greater than the maximumseparation between the base and the top plate effected by inflation ofthe enclosure.
 4. The load lifting and supporting device according toclaim 1 wherein the hinge leaves are angled outwardly with relation tosaid enclosure at all times.
 5. The load lifting and supporting deviceaccording to claim 1 wherein means are provided to aid in controllingthe movement of at least certain of the hinge leaves when the device iselevated and the hinges are to be collapsed.
 6. The load lifting andsupporting device according to claim 5 wherein the means comprisesbreaking cylinders and piston rod units operatively connected at one endto a pair of opposed members of the second hinge leaves adjacent theupper end thereof and at the opposite end to the base to move the hingeleaves outwardly.
 7. The load lifting and supporting device according toclaim 1 wherein the operative heights of said hinges is substantiallyequal to the maximum separation between the base and the top plateeffected by maximum inflation of the enclosure, and said hinges maintainsaid top plate parallel to said base.